JPH1065741A - Network repeater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure stable communication through a traffic quantity varies. SOLUTION: A transmission time measuring means 163 measures time from the start of the transmission of its OWN network to the finish of the transmission in communication mutually between networks. A timer value adjusting means 164 sets the measured value of the transmitting time measuring means to be a new time up value when the measured value of the transmitting time measuring means is larger than the time up value of a congestion monitoring timer 15 but sets the time up value of the congestion monitoring timer to be the new time up value when the measuring valve of the transmitting time measuring means is smaller than the time up value of the timer 15. When the time of the congestion monitoring timer is up, a buffer size adjusting means 165 makes a size obtained by adding the maximum frame length of transmitting data to the present buffer size of a communication buffer 162 a new buffer size. An negotiation means 166 sends the time up value and the buffer size adjusted like this to the network repeater of an opposite side to arbitrate to decide a new time up value and a buffer size.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a network relay device for relaying communication between two networks. More specifically, the present invention relates to a network relay device which is improved to optimally set communication resources such as buffers and timers on a network in accordance with a traffic amount.

[0002]

2. Description of the Related Art FIG. 7 is a diagram showing a configuration example of a network relay system. In FIG. 7, 1 is the upper network,
2 is a lower network, 3 is, for example, INS (Information)
wide-area switching network such as a network (Mation Network System), 4, 5 are routers, 6, 7 are relay devices, 8, 9
Are devices connected to nodes on the networks 1 and 2, respectively.

In such a system, the relay devices 6, 7
, A logical line of the wide area switching network 3 is established, and the two networks 1 and 2 are relayed by the established logical line.

[0004] A communication buffer is allocated to the relay device. This is because when an error occurs during transmission and data is retransmitted, the data before the error and the retransmitted data are temporarily stored in the communication buffer, or when the order of the transmission data is reversed. This is because the transmission data is temporarily stored in the communication buffer in the reverse order, and is rearranged in the correct order on the receiving side. Also, a congestion monitoring timer is assigned to the relay device in order to detect a network failure. The congestion monitoring timer has a predetermined time-up value, counts the time from the start of transmission of the own network to the end thereof, and outputs a time-up signal when transmission does not end even after counting up to the time-up value. Notifies that a network failure has occurred. When establishing a logical line, it is necessary to set the buffer size of the communication buffer and the timeout value of the congestion monitoring timer. The optimum values of the buffer size and the time-up value differ depending on the amount of traffic on the network and the bandwidth of the wide area switching network interposed between the networks.

Conventionally, an operator measures the network traffic for each system and sets a buffer size and a time-up value according to the measured value. However, in this conventional example, there is a problem that the cost required for adjustment at the time of system construction increases. Further, once the buffer size and the time-up value are set, the set values are fixed until resetting, so that there is a problem that the change in the traffic volume cannot be followed.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and measures a transmission time every time communication is performed, and sets a time-up value according to the measured time. In addition, by increasing the buffer size of the communication buffer when the congestion monitoring timer times out, it is possible to reduce the cost required for adjustment when constructing the system and to guarantee stable communication even if the traffic volume changes. It is intended to realize the device.

[0007]

SUMMARY OF THE INVENTION The present invention is a network relay device having the following configuration. (1) Counting the time from the start of transmission of the own network to the end thereof, and when the transmission does not end even after counting up to the time-up value, a time-up signal is generated and a network failure occurs. And a communication buffer that temporarily stores data to be transmitted between the networks, and performs communication between the two networks in a network relay device that relays communication between the two networks. When, the transmission time measuring means for measuring the time from the start of the transmission of the network to the end of the transmission, when the measured value of the transmission time measuring means is larger than the current time-up value of the congestion monitoring timer Sets the measured value of the transmission time measuring means as a new time-up value, and when the value is smaller, the current time of the congestion monitoring timer Timer value adjusting means for setting a new buffer value to a new time-up value, and a buffer size for setting a size obtained by adding a fixed value to the current buffer size of the communication buffer when the congestion monitoring timer times out, to a new buffer size. Adjusting means, and sending the time-up value and the buffer size adjusted by the timer value adjusting means and the buffer size adjusting means to the other network relay device, and performing arbitration with the other network relay device to obtain a new time-up value. And a negotiation means for determining a buffer size. (2) The network relay device according to (1), wherein the fixed value is a maximum frame length of transmission data.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram showing one embodiment of the present invention.
In FIG. 1, reference numeral 10 denotes a relay device. The relay device 10 is provided on each of the upper network side and the lower network side as shown in FIG. The relay device 10 relays communication between an upper network and a lower network. In the relay device 10, reference numeral 11 denotes an upper network control unit that performs protocol control of an upper network, and reference numeral 12 denotes a lower network control unit that performs protocol control of a lower network. 13 is a data bus and 14 is an address bus. Reference numeral 15 denotes a congestion monitoring timer, which counts the time from the start of the transmission of the own network to the end thereof. Notify that an error has occurred.

Reference numeral 16 denotes a processor for controlling the entire relay device. In the processor 16, reference numeral 161 denotes a transmitting means for transmitting data from its own network. A communication buffer 162 temporarily stores data to be transmitted between networks. Reference numeral 163 denotes a transmission time measuring unit that measures the time from the start of transmission of the own network to the end thereof when communication is performed between the two networks. 1
Numeral 64 is a timer value adjusting means. When the measured value of the transmission time measuring means 163 is larger than the current time-up value of the congestion monitoring timer 15, the measured value of the transmission time measuring means 163 is set as a new time-up value. Sets the current time-up value of the congestion monitoring timer 15 as a new time-up value. Reference numeral 165 denotes a buffer size adjusting means. When the congestion monitoring timer 15 times out, the communication buffer 16
A size obtained by adding a fixed value to the current buffer size of No. 2 is set as a new buffer size. Reference numeral 166 denotes a negotiation unit which sends the time-up value and the buffer size adjusted by the timer value adjusting unit 164 and the buffer size adjusting unit 165 to the partner network relay device, performs arbitration with the partner network relay device, and performs a new arbitration. Determine the time-up value and buffer size. Reference numeral 167 denotes an interrupt unit that interrupts the congestion monitoring timer 15 at regular intervals. The congestion monitoring timer 15 increments the count each time an interrupt is issued. The transmitting means 161 masks the interrupt of the interrupt means 167 when the transmission is completed, stops the congestion monitoring timer 15, and releases the interrupt mask of the interrupt means 167 when starting the transmission to release the congestion monitoring timer 15. Start

The operation of the apparatus shown in FIG. 1 will be described. FIG. 2 is a flowchart showing the operation procedure of the relay device. In FIG. 2, it is determined whether the mode is the client mode. The client mode is a mode in which the relay device continues to operate as a client. In the case of the client mode, connection processing for establishing a logical line with the partner relay device is performed. When the mode is not the client mode, the upper reception processing is performed when a communication frame is received from the upper network, and the lower reception processing is performed when a communication frame is received from the lower network. The upper receiving process is a communication from the upper network to the lower network, and the lower receiving process is the reverse communication.

FIG. 3 is a flowchart showing the procedure of the connection process. In FIG. 3, it is determined whether or not a connection is being established. If the connection is not being established, a connection is established with the other relay device, the buffer size of the communication buffer is secured at the current set value, and the time of the congestion monitoring timer is set. Set the up value to the current value.

FIG. 4 is a flowchart showing the procedure of the higher-level reception process. In each determination of the flowchart of FIG. 4, what kind of data is from the same network is identified. Each process is performed according to the identification result.

FIG. 5 is a flowchart showing a processing procedure of the lower reception processing. As shown in FIG. 5, in the relay processing to the upper network, the time from the start of transmission to the completion thereof is measured, and when the measured value exceeds the current time-up value of the congestion monitoring timer 15, this measurement is performed. The value is set as a new time-up value of the congestion monitoring timer 15. Also,
When the congestion monitoring timer 15 times out, it is recognized that congestion has occurred in the network, and a value obtained by adding a fixed value to the buffer size of the communication buffer at that time is set as a new buffer size. The congestion referred to here is a state in which the network is congested. The fixed value is, for example, the maximum frame length of the transmission data of the network. As a result, the buffer capacity is increased for each frame.

FIG. 6 is a flowchart showing a negotiation processing procedure. The time-up value and the buffer size (these are used as parameters) obtained in the processing shown in FIG. 5 are sent to the partner relay device, arbitration is performed with the partner relay device, and the communication buffer 162 is updated with new parameters obtained as a result. And the time-up value of the congestion monitoring timer 15 are reset. Thus, the buffer size and the time-up value are adjusted.

[0015]

According to the present invention, a transmission time is measured each time communication is performed, a time-up value of a congestion monitoring timer is set according to the measured time, and a communication buffer is set when the congestion monitoring timer times out. Buffer size has been increased. As a result, the time-up value of the congestion monitoring timer and the buffer size of the communication buffer can be automatically tuned according to the traffic volume. Therefore, stable communication can be guaranteed even when the traffic volume increases. Further, since tuning at the time of system construction becomes unnecessary, the construction cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of the present invention.

FIG. 2 is an explanatory diagram of the operation of the apparatus of FIG. 1;

FIG. 3 is an operation explanatory diagram of the device of FIG. 1;

FIG. 4 is an explanatory diagram of the operation of the device of FIG. 1;

FIG. 5 is an operation explanatory diagram of the device of FIG. 1;

FIG. 6 is an explanatory diagram of the operation of the device of FIG. 1;

FIG. 7 is a diagram illustrating a configuration example of a network relay system.

[Explanation of symbols]

 1, network 10 relay device 15 congestion monitoring timer 16 processor 161 transmitting means 162 communication buffer 163 transmission time measuring means 164 timer value adjusting means 165 buffer size adjusting means 166 negotiation means

Claims (2)

[Claims] The present invention counts the time from the start of transmission of the own network to the end thereof, and if the transmission does not end even after counting up to the time-up value, a time-up signal is generated to cause a failure in the network. A congestion monitoring timer for notifying that communication has been performed, and a communication buffer for temporarily storing data to be transmitted between the networks, and a network relay device for relaying communication between the two networks. When performing, the transmission time measurement means for measuring the time from the start of the transmission of its own network to the end, the measurement value of the transmission time measurement means than the current time-up value of the congestion monitoring timer If it is larger, the measured value of the transmission time measuring means is set as a new time-up value, and if smaller, the current value of the congestion monitoring timer is A timer value adjusting means for setting a time-up value to a new time-up value; and a buffer for setting a size obtained by adding a fixed value to the current buffer size of the communication buffer when the congestion monitoring timer times out, to a new buffer size. Size adjustment means, and sends the time-up value and the buffer size adjusted by the timer value adjustment means and the buffer size adjustment means to the other network relay device, and performs arbitration with the other network relay device to perform new time-up. A network relay device comprising: negotiation means for determining a value and a buffer size. 2. The network relay device according to claim 1, wherein the fixed value is a maximum frame length of transmission data.